In a Dutch oven or heavy stock pot, heat the oil over medium heat. Sauté the onion until translucent and just starting to brown. Add the garlic and cook for 1 minute, stirring frequently to keep the garlic from burning.

Stir in the harissa, cinnamon, and coriander, and cook for 30 seconds to release the fragrance from the spices. Add the squash and tomatoes, stir to incorporate the spices, and add 2 cups of water. Bring to a boil, then reduce heat to simmer, cover, and cook for 30 minutes, stirring a few times.

Add the chickpeas, green peas, and parsley, and continue to cook, uncovered, for 10 minutes. Taste, and adjust seasoning with salt and pepper. Serve hot, over couscous or rice.